title: Ethyl 1''-benzyl-1'-methyl-2''-oxodi-spiro-[indeno-[1,2-b]quinoxaline-11,3'-pyrrolidine-2',3''-indoline]-4'-carboxyl-ate.
abstract: In the title compound, C36H30N4O3, the quinoxaline-indene system is roughly planar, with a maximum deviation from the mean plane of 0.218 Å for the C atom shared with the central pyrrolidine ring. This latter ring forms dihedral angles of 84.54 (7) and 83.91 (8)° with the quinoxaline-indene system and the indole ring, respectively. The central pyrrolidine ring has an envelope conformation with the N atom as the flap, while the pyrrolidine and five-membered rings of the indole group adopt twisted conformation and envelope (with the C atom bearing the quinoxaline-indene system as the flap) conformations, respectively. In the crystal, mol-ecules are linked via weak C-H⋯N hydrogen bonds, forming a chain running along [100].
authors.affiliation: Department of Physics, S.M.K. Fomra Institute of Technology, Thaiyur, Chennai 603 103, India.
authors.forename: Piskala Subburaman
authors.initials: PS
authors.lastname: Kannan
authors.forename: Srinu
authors.initials: S
authors.lastname: Lanka
authors.forename: Sathiah
authors.initials: S
authors.lastname: Thennarasu
authors.forename: Elumalai
authors.initials: E
authors.lastname: Govindan
authors.forename: Arunachalathevar
authors.initials: A
authors.lastname: Subbiahpandi